Eleoteio motoe controllim apparatus



(No Model.) 2 Sheets-Sheet 1.

P. E. HERDMAN.

ELEUTRIC MOTOR CONTROLLING APPARATUS.

No. 519,124. Patented May 1,1894.

(No Model.) 2 Sheets-Sheet 2.

P. E. HERDMAN. ELEGTRIU MOTOR CONTROLLING APPARATUS.

No. 519,124. Patented May 1,1894.

WIT/(E6 656 I ////E/7 rm? 'fmw UNITED STATES PATENT OFFICE.

FRANK E. HERDMAN, OF INDIANAPOLIS, INDIANAM ELECTRlC-MOTOR-CONTROLLI NGAPPARATUS.

SPECIFICATION forming part of Letters Patent No. 519,124, dated May1894- Application filed October 20, 1892. Renewed January 11, 189L1-Serial No. 1 (No model) To all whom it may concern;

Be it known that I, FRANK E. HERDMAN, a citizen of the United. States,residing at Indianapolis, county of Marion, and State of Indiana, haveinvented a new and useful Improvement in Electric-Motor-0ontrollingApparatus, of which the following is afull, clear, and exactdescription, reference being had to the accompanying drawings, whichform a part of this specification.

My invention relates specifically to the combination and arrangement ofdevices whereby the admission of the current to the motor is controlled.

In the accompanying drawings Figure 1 represents a side elevation of'myapparatus, sufficientto disclose my invention. Fig. 2 is a diagrammaticView showing the direction of the various circuits.

M is the motor provided with the shaft m, for the transmission of power,the field of the motor being in direct electrical connection with thesource of current supply through binding posts A and 3, and the armatureof the motor being in electrical connection with binding post 5, whichis in electrical connection with brush 8 of the switch, I, the switch,I, being in electrical connection with both poles of current supply; andthe resistances R are in electrical connection with brush 7 of switch,I, and said resistances, through arm, J, are in connection with thearmature of the motor.

G is the operating arm for the switch, I.

U is a double pole switch, the contacts 17 and 18 of which are inelectrical connection with the source of current supply. To the arm J isattached the core of a solenoid, 25, and dash pot, 26. The solenoid isin electrical connection with the contacts, U and U of switch U. In theelectrical connection between contact, U and the solenoid is thecontact, 27, in contact with brush, 28. The

electrical connection between arm J and the allow the contents to passfrom one side to the other of the piston.

To the bottom of the dash pot are connected two pipes, 102 and 103, onecarrying the check valve 30 and the other carrylng the small cock 31. Inthe main pipe, 104., to which these converge and which extends from oneside of the piston to the other, is cook 32, and also cook, 33. It isdesirable that when the current is cut off from the motor the arm J,should travel back over the resistances rapidly, and to accomplishthisthe oil must rapidly pass from the upper side of the piston to theunder side, and to permit this, the check valve, 30, opens upward sothat while arm J is returning it opens, allowing the Oll rapidly toenter below the piston. The speed at which the oil passes can becontrolled by means of the adjusting cook 32. As the passage of the arm,J, over the resistances, when the currentis admitted, is desired to beslow, the passage of the oil from beneath the piston of the dash pot tothe upper side must be slow. To accomplish this the check valve, 30,closes, and the cock can be adjusted to control as desired. Link 125connects cook 33 with the lever T, whlch lever 1s in connection with theoperative mechanlsm. Cock 33 is so adjusted that when the lever T is inits central position this cock is closed. Either throw of the lever Tfrom the center opens this cock. If the lever T be operated so that itsswitch connecting end is lowered, the switch U is brought in contactwith contacts U and U and at the same time the cook 33 is opened. Thecircuit is now closed through the solenoid 25, which causes it to actforcing the arm over the resistances against the dash pot 26, and thespeed of the movement of arm J is regulated by the adjustment of cook31. When the lever T is operated to bring switch U to a centralposition, breaking the circuit With contacts U U thereby breaking thecircuit of the solenoid 25,-the same movement of lever T brings the cook33 to a central position. When in this position the 011 located in thedash pot is prevented from passing to one side or the other, and the armJ 1S held in a fixed position. If the lever T be moved farther the cook33 is operated, but in the opposite direction from that when the switchis in contact with the contacts, U and U When open in this direction,the weight of the solenoid core draws the lever J back, the speed atwhich it is drawn back being governed by the speed at which the liquidin the dash pot is permitted to pass from one side to the other.

In case the current passing through the main circuit becomes excessiveand beyond what should be permitted to enter the motor, the weight ofthe core of the solenoid 29 is so adjusted that the strength of thesolenoid at this time would become such as to draw said core, in thusdrawing brush 28 oh": of contact with contact 27 and breaking theelectrical circuit through the solenoid 25 and at the same time openingcook 34: to which said core is connected by lever 126, link 127 and bellcrank 128, allowing the oil to pass freely from one side to the other ofthe dash pot. By this arrangement, if for any reason the current in themotor becomes too great the current is automatically cut off from themotor, thereby preventing damage to the motor. Under such conditionswhen the arm J is returned the current would be broken through thesolenoid 29, thereby permitting the core to return, closing the circuitthrough the solenoid 25, which would again act and throw the arm J overthe resistance contacts the same as before, so that as long as the leveris kept ofi? of the center, and the current is too great for thearmature this movement will be kept up. To obviate this to the operatingbar G is attached an inclined plane 35, and upon this inclined planerests a roller -10 having a lever 36 pivoted at 37, the bar end of thislever 36 coming in contact with projection 38 upon the core of thesolenoid 29. When the solenoid 29 is operated and core drawn, the lever36 would rise behind the projection 38 and thereby prevent the return ofthe core, and in consequence the circuit could not be again closedthrough the solenoid 25 until the operating bar G had been brought tothe center (at which time the current will be cut out of the armaturecircuit) which would cause the active end of lever 36 to rise, freeingthe projection 38 from said lever.

Having now fully described my invention, what I'claim, and desire toprotect by Letters Patent, is-- 1. The combination with a source ofcurrent supply, and an electric motor of an armature current controllingswitch, resistances in circuit with said switch, an arm in circuit withthe armature of the motor and adapted to travel over said resistances,asolenoid,the core of which is connected to said arm, an independentsolenoid controlling switch, elec: tric connection between said switchand current supply and between said switch and solenoid and independentoperating devices for each of said switches.

2. The combination with a source of current supply and an electric motorof an armature circuit controlling switch, resistances in circuit withsaid switch, an arm adapted to travel over said resistances, electricconnection between said arm and armature of motor, a solenoid throughwhich said connection passes, the core of said solenoid carrying abrush, a solenoid the core of which is connected with said resistancearm, a solenoid controlling switch, electric connection be tween saidswitch and a contact as 27, and electrical connection between saidsolenoid and brush 28 carried by first mentioned solenoid core.

3. The combination with a source of current supply, and electric motor,a resistance interposed between the armature of the motor and source ofcurrent supply, a resistance arm in electric connection with saidresistance and with said armature of the motor, a solenoid the core ofwhich is connected with said arm, electrical connection between saidsolenoid and the source of current supply, a dash pot, the piston ofwhich is connected with said resistance arm, a cylinder for sa d pistonadapted to receive and contain a fluid and pipes leading from the lowerto the upper portion of said cylinder.

4. The combination with a source of current supply, an electric motor,resistances mterposed between the armature of the motor and source ofcurrent supply, a resistance arm in electrical connection with saidresistance and with said armature of the motor, a solenoid the core ofwhich is connected with said arm, electrical connection between saidsolenoid and the source of current supply, a dash pot, the piston ofwhich is connected with said resistance arm, a cylinder for said pistonadapted to receive and contain a fluid, a pipe leading from the upper tothe lower portion of said cylinder, said pipe terminating in two branchpipes, cocks on said pipes, a cock on the main pipe and the controllingcock on the main pipe also.

5. The combination with a source of current supply and an electric motorof an armature current controlling switch, resistances in circuit withsaid switch, an arm in circuit with the armature of the motor andadapted to travel over said resistances, a solenoid the core of which isconnected to said arm, an independent solenoid controlling switch,electric connection between said switch and current supply and betweensaid switch and SO lenoid and independent operating devices for each ofsaid switches, a dash pot connected to said resistance arm, a cylinderadapted to hold liquid, a pipe leading from the upper to the lowerportion of said cylinder, a cock on said pipe, connection between saidcock and the solenoid controlling the switch operating device.

6. The combination with a source of current supply and an electric motorof an armature circuit controlling switch, resistances in circuit withsaid switch, an arm adapted to travel over said resistances, in circuitwith said switch, an arm adapted to travel over said resistances,electric connection between said arm and armature of motor, a solenoidthrough which said connection passes, the core of said solenoid carryinga brush, a solenoid, the core of which is connected with said resistancearm, a solenoid controlling switch electric connection between saidswitch and a contact as 27, and electrical connection between saidsolenoid and brush 28 carried by first mentioned solenoid core, a dashpot, the piston of which is connected to the resistance arm, a cylinderadapted to contain liquid, a pipe connecting the bottom and top of saidcylinder, avalve in said pipe, a lever connected to the core of thefirst mentioned solenoid and intermediate connection between said leverand said valve.

7. The combination with a source of current supply and an electric motorof an armature circuit controlling switch, resistances in circuit withsaid switch, an arm adapted to travel over said resistances, electricconnection between said arm and armature of motor, a solenoid throughwhich said connection passes, the core of said solenoid carrying abrush, a solenoid the core of which is connected with said resistancearm, a solenoid controlling switch, electric connection between saidswitch and a contact as 27, and electrical connection between saidsolenoid and brush 28 carried by first mentioned solenoid core, anoperating bar for operating the armature controlling switch, an inclinedplane as 35, attached to said bar said inclined plane having a leverpivoted to a projection on the core of the first mentioned solenoidinline with the end of said lever.

In testimony of which invention I have hereunto set my hand.

FRANK E. HERDMAN.

Witnesses:

W. V. MARTIN, JOSEPH 000K.

